Electrical connector devices having improved terminal means

ABSTRACT

AN ELECTRICAL CONNECTOR DEVICE INCLUDING A PROTECTIVE HOUSING WITHIN WHICH IS POSITIONED AN INSULATOR BODY WHICH SUPPORTS REMOVABLE TERMINAL-CONTACT ELEMENTS HAVING SPRING METAL RETAINING CLIPS INSERTABLE INTO SLOTS FORMED IN THE TERMINAL BLOCK PORTIONS OF THE ELEMENTS TO SECURE THE ELEMENTS IN THE INSULATOR BODY.

Feb. `16, 1971 `Acz. J. GILBERTI 3,564,484

l.ELECTRICAL CONNECTOR DEVICES HAVING IMPROVED vTERMlNAL MEANS Filed March v20, 1968 j' 53,; i251@ *j j i j' A- z2 2a f4 a4 sa 1% 74a ff@ 14 0' a f z-'N 577@ 4" '41 j i? '.30 93 7 2% 74 9052 40 105 Il 52 i 38 .3l 40 6 lll/2 23 ."il: f ull. 55W L United States Patent Oihce 3,564,484 Patented Feb. 16, 1971 U.S. Cl. 339-136 6 Claims ABSTRACT` OF THE DISCLOSURE An electrical connector device including a protective housing within which is positioned an insulator body which supports removable terminal-contact elements having spring metal retaining clips insertable into slots formed in the terminal block portions of the elements to secure the elements in the insulator body.

BACKGROUND OF THE INVENTION This invention relates to electrical connector devices and more particularly to those devices having improved means for retaining the terminal-contact elements in the insulator body members.

One well known type of electrical connector device is that which is especially suitable for high amperage ratings. This type of heavy-duty connector device has broad, flat contact blades and mating receptacle contacts which insure good electrical connection between the plug and the receptacle. The contacts are permanently secured to the terminal blocks to form the terminal-contact elements which are carried by the corresponding insulator bodies. The insulator bodies of both the plug and receptacle have circumferentially spaced axially extending polygonal sockets therein which receive the complementary shaped terminal block portion of the terminal-contact elements. This type of construction allows the device to have the feature of selective initial Contact conguration set-up to achieve controlled noninterchangeability between devices of diierent electrical capacities, such as voltages. The various congurations may be set up by mounting each terminal-contact element in the desired angular position in the sockets of the insulator body. The connector devices are completed by securing the insulator bodies within their respective protective housings which comprise metal shells usually made of a cast aluminum alloy or other suitable material which is both strong and light in weight. A power cable enters the receptacle through a conduit and an equipment supply cable enters the plug, the conductors thereof being secured to the terminal-contact elements in a known manner as by being introduced axially into axial openings formed in the end of the terminal blocks. The conductors are captured in the terminal block by means of a usual transversely movable threaded stud.

In the connector devices constructed in accordance with the known prior art, the terminal-contact elements are retained in their individual molded sockets by means of the threaded stud which extends through a transverse opening formed in the insulator body to prevent longitudinal movement of the terminal block within the socket. It is necessary, in one size connector ot this type, to maintain a minimum 3/8 inch clearance between the electrically grounded metal shell and the ends of the threaded studs capturing the line and neutral conductors in order to prevent arcing and current leakage to the metal shell with the resultant shock hazard condition caused thereby. The length of the threaded stud, however, must also be selected to allow the end thereof to extend through the opening in the insulator body when arminimum size conductor is captured in the terminal block to prevent the terminalcontact element from falling out. Thus, problems are often encountered when a maximum size conductor is used (for example No. 6` AWG) since the kerfed end of the threaded stud will extend so far out of the terminal block as to reduce the required 1%; inch clearance. If the threaded stud were reduced in length to prevent arcing and a minimum size conductor is used, the stud will not retain the terminal-contact element in position in the socket.

SUMMARY OF THE INVENTION Accordingly, it is the primary object of this invention to provide in an electrical connector an improved terminalcontact element retaining arrangement including retaining means which will reliably maintain the required clearance between the current carrying portions of the elements and the usual connector metal shell when large diameter conductors are connected to the elements, while preventing undesired disassembly ont the elements from the connector when small diameter conductors are connected to the elements.

Another object of this invention is to provide retaining means as set forth in the preceding paragraph, which is inexpensive and may be quickly and easily effectuated to position and retain the terminal block of the element within the insulator body.

A further object is to provide in the foregoing improved arrangement an insulator body which is formed to receive a retaining clip, which is a part of the retaining means, and to resist any tendency of the clip to be dislodged due to vibrations or sudden shocks.

To accomplish these objects, in one form an electrical connector device is provided which comprises: a protective metal housing; insulator means positioned within the housing; terminal means removably positioned within the insulator means; and means for retaining the terminal means in the insulator means including a retaining member mountable upon the terminal means and cooperating with the insulator means to substantially immovably secure the terminal means in the insulator means.

BRIEF DESCRIPTION OF THE DRAWING Other objects and further details of that which I believe to be novel and my invention will become clear from the following description and claims taken with the accompanying drawing, wherein:

FIG. l is a side elevational view of a heavy-duty plug engaged with a suitable receptacle;

FIG. 2 is a partial sectional view of the plug and receptacle showing the mating terminal-contact elements and the manner in which they are retained in the insulator bodies.

FIG. 3 is a sectional view taken substantially along line 3-3 of FIG. 2, showing the retaining clips straddling the terminal block;

FIG. 4 is a sectional view taken substantially along line 4-4 of FIG. 2;

FIG. 5 is an enlarged sectional view showing more clearly the manner in which the retaining clip secures the terminal-contact element within the insulator body, and further showing the construction of the insulator body for preventing dislodgement of the retaining clip.

FIG. 6 is a sectional view taken substantially along line 6 6 of FIG. 5 and 1FIG. 7 is an enlarged perspective view of the retaining c ip.

DESCRIPTION OF THE PREFERRED EMBODIMENT Turning now to the drawing, there is illustrated in FIGS. l and 2 a heavy-duty connector device including a plug and a receptacle 12 secured together by means of a screw-on collar 14. A power cable 16 passes through conduit C to the receptacle, and an equipment supply cable 18 is secured to the plug. A cable clamp 20` threadedly engage with the metal shell of the plug rmly grips the cable 18 and effectively protects the plug terminals from any axial forces that may be placed on the cable.

The plug 10 includes a metal shell 22 preferably made of an aluminum alloy chosen for its characteristic strength and lightweight. Several circumferentially spaced, radially inwardly extending lugs 24 are formed on the interior wall of the shell each having a tapped opening 26 therein to receive suitable securing screws 28. A circumferential ange 30 is formed on the exterior surface of the shell 22 to limit axial movement of the screw-0n collar 14. The shell also supports an external key 32 adjacent the fOrward end thereof to assist in positioning the plug 10 relative to the receptacle 12 during engagement,

An insulator body 34 made of a suitable plastic material is mounted in the shell by means of the securing screws 28 which pass through axial openings 36 formed in the body 34 and are threadedly engaged in the tapped openings 26. Circumferentially spaced, axially extending sockets 38 of substantially square cross-section are formed in the insulator body to receive the terminal block portions 40 of the male terminal-contact elements 41.

Each terminal block 40 is made of metal and is of substantially square cross-section so as to be mounted in its complementary socket 38. An axial opening 42 is formed in one end thereof to receive a conductor 44, and a transverse threaded opening 46 passes though one side of the block into the axial opening 42, with partial threads being formed on the side walls of the axial opening 46 to receive a threaded stud 48 in a known manner. At the other end of the terminal block there is dened a slot 50 in which a flat contact blade 52 is mounted (note FIG. 4). The blade is permanently secured in the terminal block, to form the terminal-contact element 41, by means of deforming a portion 54 thereof with a suitable punch through a transverse aperture 56 in the terminal block.

The receptacle 12 comprises a sectional metal shell including: a forward section 58a having an externally threaded mating end 60, an axially extending keyway 62 positioned to receive the external key 32 when the plug and receptacle are properly aligned, and radially inwardly extending spaced lugs 64 having openings 66 formed therein through which elongated securing screws 68 may pass; a central section 58b which may be secured to the 'rst section by means of suitable securing screws 70; and a rear wall mountable section 58e` securable to the central section by means of securing screws 72.

A two-part insulator body 74 is supported within the sectional shell 58 by means of the elongated securing screws 68 which pass through an insulator cover portion 74a and are threadedly engaged in an insulator straddling portion 74b, the two insulator body portions straddling the radially inwardly extending lugs 64. A central securing screw 76 preferably made of plastic passes through a central axial opening 77 in the insulator cover portion 74a and is threadedly engaged in a tapped bore 78 in the insulator mounting portion 74b to maintain these two insulator body portions together. The insulator mounting portion 74b has sockets 80 defined therein to receive the terminal blocks 82 of the female terminal-contact elements 84. As illustrated in FIG. 4 the sockets 80 are formed with shoulders 86 which prevent the receptacle contacts 88 from passing completely there through. T he insulator cover portion defines chambers 90 positioned to be aligned with the sockets 80 when the insulator body portions 74a and 74b are secured together to receive the receptacle contacts 88. The chambers are constructed to insure that any arcing between the male and female contacts during engagement and disengagement of the connector device is completely conned therein.

The receptacle contacts 88, made of a suitable spring metal, are generally U-shaped to capture the flat Contact blade 52. The contacts 88 are permanently secured to the terminal blocks 82 by means of a central rivet 92. A threaded stud 94 is engaged in a transverse tapped opening in each terminal block 82 in a known manner to capture the conductor 96 in the axial opening 98.

The terminal contact elements 41 and 84 are retained in the sockets 38 and 80, respectively, in the unique manner illustrated in FIGS. 3, 5 and 6. Although these figures illustrate the plug, it should be kept in mind that it also refers to the receptacle construction except as otherwise stated. Radial passages 100 pass from the external surface of the insulator body 34 to the sockets 38 each passage including a sloped wall 102 of approximately 8 which terminates in a recessed Seat 104. In order to prevent the terminal contact elements 41 and 84 from passing through the respective insulator bodies 34 and 74b, shoulders 106 nad 86 have been provided in the sockets. Tapered milled slots 108 are formed in the side walls ot each terminal block and are positioned to be in substantial alignment with the seat 104 when the block is properly located in the socket.

A retaining clip 110 made of a suitable spring metal, clearly shown in FIG. 7, is formed with inwardly tapered legs 112 terminating in outwardly tapered ramp portions 114. When assembling the plug 10, each terminal-contact element 41 selected for a particular set-up configuration is inserted into a socket 38 until it abuts the shoulder 106. Then the legs 112 of the retaining clip 68 are urged into the tapered slots 108 as the clip is moved down the sloped wall 102 (note the representations shown in dot-dash lines in FIG. 5 and 6) until it snaps into place about the terminal block and into the seat 104. The ramp portions 114 allow the clip to be introduced into the slots 108 and cause the legs to be sprung outwardly; however, it should be pointed out that when the retaining clip is in position straddling the terminal block 40 it is in an unstressed condition.

With the retaining clips 110 in position the terminalcontact elements 41 and 84 are securely retained in the insulator bodies 34 and 74b while reliably maintaining the required clearance between current carrying parts of the contact-terminal elements and the metal shells 22 and 58. This obtains because the clips 110 prevent axial movement of the contact-terminal elements in one axial direction because of interference of their bight portions with walls of the seats 104, and the shoulders 86 and 106, respectively, prevent movement of the elements in the other axial direction, thereby effectively positioning and immovably retaining the elements in position, until the clips 110 are removed. It is impossible for the retaining clip to back out due to sudden shocks or vibrations, since to do so it must move out of seat 104 and up the sloped wall 102.

It should be understood that the present disclosure has been made only by way of example, and that numerous changes in details of construction and the combination and arrangement of parts may be resorted to without departing from the true spirit and the scope of the invention.

What is claimed is:

1. An electrical connector device comprising: a protective metal housing; insulator means positioned within said housing; terminal means removably positioned within said insulator means; and resilient retaining means mounted upon said terminal means and cooperating with said insulator means to substantially limit movement of said terminal means in one axial direction; said terminal means including a polygonal terminal block having slots defined in opposite faces thereof to receive portions of said retaining means, said slots being tapered toward one another and said retaining means includes a generally U- shaped clip made of spring metal having inwardly tapered legs constituting said portions.

2. The electrical connector device defined in claim 1 wherein said clip has outwardly tapered ramp portions located at the ends of said legs.

3. An electrical connector device comprising: a protective metal housing; insulator means positioned within said housing; terminal means removably positioned within said insulator means; resilient retaining means mounted upon said terminal means and cooperating with said insulator means to substantially limit movement of said terminal means in one axial direction; said terminal means having a portion for receiving portions of said retaining means of substantially equal size thereto; said terminal means having a portion accessible from the exterior of said insulator means for wiring whereby it is not necessary to remove said terminal means from said insulator means for wiring; said insulator means defining an axial socket therein to receive said terminal means, said socket being of a polygonal cross-section, receiving a polygonal portion of said terminal means and having a transversely extending shoulder at one end to limit axial movement of said terminal means in the other axial direction; and said insulator means defining a transverse opening therein communicating with said socket through which said retaining means may be introduced to said terminal means.

4. The electrical connector device defined in claim 3 wherein said portion of said terminal means comprises a terminal block having slots defined in opposite faces thereof to receive portions of said retaining means, and said insulator means defines a recessed seat communicating with said transverse opening, said seat being located to be aligned with said slots to receive a portion of said retaining means when said terminal means is positioned within said socket.

5. An electrical connector device comprising: a protective metal housing; insulator means positioned within said housing; terminal means removably positioned within said insulator means; and resilient retaining means mounted upon said terminal means and cooperating with said insulator means to substantially limit movement of said terminal means in one axial direction; said insulator means defining an axial socket therein to receive said terminal means; said socket being of polygonal cross-section and having a transversely extending shoulder at one end to limit axial movement of said terminal means in the other axial direction; said insulator means defining a transverse opening therein communicating with said socket through which said retaining means may be introduced to said terminal means; said terminal means including a terminal block having slots defined in opposite faces thereof to receive portions of said retaining means; said insulator means defining a recessed seat communicating with said transverse opening, said seat being located to be aligned with said slots to receive a portion of said retaining means when said terminal means is positioned within said socket; said slots being tapered toward one another; and Said retaining means including a generally U-shaped clip made of spring metal having inwardly tapered legs constituting said portions of said retaining means and a bight constituting said portion of said retaining means.

6. The electrical connector device defined in claim 5 wherein said insulator means defines a sloped wall leading downwardly from the external surface of said insulator means to said seat to prevent fallout of said clip.

References Cited UNITED STATES PATENTS 3,101,983 8/1963 van Herssen 339-217X 2,307,972 1/1943 Strunk 339-185 2,411,861 12/1946 Anteny,1r.,eta1. 339-89X 3,046,512 7/1962 Rernke et a1 339-2172( 3,122,407 2/1964 cowl 339-217 FOREIGN PATENTS 163,279 6/1955 Australie 339-2171 890,614 11/1943 France 339-217 RICHARD E. MOORE, Primary Examiner U.S. Cl. X.R. 

